“ Measles is unlike other childhood viruses that come and go. In severe cases it can cause pneumonia. About 1 in 1,000 patients develops encephalitis, or swelling of the brain, and there are 1 or 2 deaths per 1,000, according to the Centers for Disease Control and Prevention.
The virus can wipe out the immune system, a complication called “immune amnesia.”
When we get sick with viruses or bacteria, our immune systems have the ability to form memories that quickly allow them to recognize and respond to the pathogens if they’re encountered again.
Measles targets cells in the body, such as plasma cells and memory cells, that contain those immunologic memories, destroying some of them in the process.
“Nobody escapes this,” said Dr. Michael Mina, a vaccine expert and former professor of epidemiology at Harvard T.H. Chan School of Public Health, who has led some of the research in the field.
In a 2019 study, Mina and his team found that a measles infection can wreck anywhere from 11% to 73% of a person’s antibody stockpile, depending on how severe the infection. That means that if people had 100 antibodies to chickenpox before they had measles, they may be left with just 50 after measles infections, potentially making them more vulnerable to catching it and getting sicker.
Akiko Iwasaki, a professor of immunology at the Yale School of Medicine, said: “That’s why it’s called amnesia. We forget who the enemies are.” ”
http://www.nbcnews.com/health/health-news/measles-immune-system-brain-swelling-long-term-rcna195918
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